Hospital bed

ABSTRACT

A hospital bed has a mattress support whose upper surface is formed at each end by a primary flap hinged toward the center of the upper surface. A secondary flap is pivotally secured to the primary flap so that a bladder in the mattress support beneath the secondary flap can be inflated to lift this flap and elevate the head or feet of the person in the bed. The flap may be formed of a pair of hinged-together sections. The mattress support is held on a base by means of bladders which are transversely spaced and can be inflated to tip the entire support about a horizontal longitudinal axis of the bed. A leg is provided in the middle of each side of the base of the bed, and at least the legs at the head and foot of the bed are of adjustable length so that the entire bed can be tipped if desired.

United States Patent 11 1 1111 3,879,772 Pol 1 1 Apr. 29, 1975 [54] HOSPITAL BED 3.750.200 8/1973 Hirmann /68 3. 2 [75] Inventor: Lucien Pol, Marseille. France 781 9 8 H1974 Swine 5/68 ASSignee: Socicte Provencale de Fabrications Prinuu-y E a niner casmir Nunberg M iC -C g Alto/nay. Agent, or Firn1Karl F. Ross; Herbert Marseilles. France Dubno [22] Filed: Jan. 28. 1974 1211 Appl. No: 437,329 [57] ABSTRACT A hospital bed has a mattress support whose upper no] Forei n A cation Prior Dam surface is formed at each end by a primary flap hinged g pp 3 toward the center of the upper surface. A secondary Jan. 30. 1973 France 73.0388] flap is pivotally secured to the primary flap so that a a bladder in the mattress support beneath the secondary 3/683 5/623 5/63? flap can be inflated to lift this flap and elevate the 5/90 head or feet of the person in the bed. The flap may be [51] f- Cl 1: 7/10; Folb 21/00 formed of a pair of hinged-together sections. The mat [58] Fleld of Search 5/61- 66*691 tress support is held on a base by means of bladders 128/33 which are transversely spaced and can be inflated to tip the entire support about a horizontal longitudinal [561 References C'ted axis of the bed. A leg is provided in the middle of each UNITED STATES PATENTS side of the base of the bed. and at least the legs at the 3.213.469 10/1965 Beeman 5/68 head and foot of the bed are of adjustable length so 3.305.870 2/1907 Hutt t 5/63 that the entire bed can be tipped if desired. 3.300.717 3/1967 Black 5/68 3.724.003 4/1973 Ellwangcr ct al. 5/63 11 Llalmsi 13 Drawmg Flgures 1a 7a 11 7 6 i s B a 45 1 T 7 I 1* T 48 a; I/ 38 14/ I, .7 l

r I 37 A 1311 a 3 14a 2 1 P1 29 P2. o 33 PATENTEDAPRZQiQYS SHEET 1 [IF 7- HOSPITAL BED FIELD OF THE INVENTION The present invention relates to an adjustable hospital bed of high versatility and low cost.

BACKGROUND OF THE INVENTION It is generally necessary to provide a hospital bed or the like with means allowing adjustment of the mattress so as to give the patient maximum comfort. Thus it is necessary to be able to raise the head part of the mattress so as to allow him to sit up and eat in bed or to watch television, or similarly to raise the foot portion so as to make the patient comfortable. In addition it is advantageous to be able to raise the entire mattress so as to facilitate examination and rehabilitation of the patient. It also is frequently necessary to be able to tip the entire mattress about either a transverse or longitudinal axis to arrest bleeding or to otherwise medically aid the patient.

Beds proposed to satisfy these requirements are often complicated and very expensive. The generally comprise various electric motors which have threaded spindles that are screwed into nuts in various parts of the bed so that when rotated these parts of the bed are moved relative to each other to effect the various displacements necessary. Such systems of course are prone to failure and require frequent maintenance.

OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide an improved bed.

Another object is the provision of an improved hospital bed which is capable of adjustment in the abovedescribed manner.

A further object is the provision of such a bed which is relatively simple and which can be made relatively inexpensively.

Yet another object is the provision of a hospital bed which can be transported from place to place with relative ease.

SUMMARY OF THE INVENTION I attain these objects according to the present invention in a bed comprising a mattress support whose elongated upper surface has longitudinal ends each formed by a primary flap which is hinged to pivot about a transverse axis inwardly of the longitudinal end. The mattress support lies on a base through the intermediary of at least two transversely spaced inflatable bladders which can be inflated together to raise the entire support from the base, or separately to tip the support relative to the base. A secondary flap is arranged underneath each of the primary flaps and is pivotally fixed thereto, so that the primary flap forms with the secondary flap on outwardly open V having its vertex at the respective hinge. Another bladder is provided between each of the secondary flaps and the support so that when inflated it raises the respective primary flap and thereby raises that end of the upper surface.

According to yet another feature of this invention each flap has a pair of flat sections hinged together about an axis transverse to the longitudinal axis of the support surface and intermediate between the respective hinge and the respective end of the primary flap. When the primary flap is raised, therefore, the two sections are able to pivot relative to one another so that the longitudinally outer end of the outer section can remain in contact with the support, thereby forming a convenient leg rest. Similarly means can be provided to rigidly secure the two flaps together so as to raise the entire primary flap and thereby provide a back rest allowing the patient to eat in bed or read.

The arrangement according to the present invention can be made relatively cheaply as the actuating bladders are very inexpensive to make and have a relatively long service life. All that is needed is a single small air pump and a distributing valve to operate the various bladders so that this single pump or blower can operate all of the various bladders which serve to raise and tilt the bed. Obviously such a construction is relatively inexpensive allowing such a bed to be bought by a private person without undue hardship.

According to further features of the invention the bed has four legs, each arranged in the middle of a respective side, not in a corner as is conventional. The end legs are of adjustable effective length, that is the length between the lower end of the leg and the base. Thus it is possible to tilt the entire bed by lengthening one of the end legs and shortening the other. The legs are all provided with casters according to the present invention. In addition it is possible to lengthen and shorten the side legs so as to lower the bed almost to the floor level, and to be able to adjust the bed so that it stands perfectly level on uneven ground or a nonhorizontal floor. The provision of casters or wheels on the lower end of the legs allows this bed to be used readily to transport a patient from one division of a hospital to another.

The mattress support according to the present invention has an upper surface or wall which is generally rectangular, and is formed as a rigid frame or chassis underneath this upper surface. The base is formed with a pair of recesses adapted to receive the abovementioned secondary flaps which are pushed upwardly by the second bladders to raise the end sections of the bed. To this end the bottom of the support is formed with a pair of abutment surfaces which are receivable in the recesses in the base, and on which lie the second bladders. The provision of the secondary flaps pivotally linked to the primary flaps eliminates many complications, in that the bladders hardly ever extend appreciably above the support, leaving these bladders protected from puncture at all times.

BRIEF DESCRIPTION OF THE DRAWING The above and other objects, features, and advantages of the present invention will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

Flg. 1 is a longitudinal section through a bed according to the present invention;

FIG. 2 is a longitudinal section through the bed in another operative position;

FIG. 3 is a side view of the bed, partly in section, in yet another operative position;

FIG. 4 is a section taken along lines lV-lV of FIG.

FIG. 5 is a top view in greatly reduced scale of the bed according to the present invention;

FIG. 6 is a similar reduced-scale top view of another bed according to the present invention;

FIGS. 7, 8 and 9 are side elevational views of the bed of FIG. 6 in three different operative positions;

FIG. 10 is a longitudinal section through the bed of FIG. 6;

FIG. 11 is a section taken along line Xl-Xl of FIG. 10;

FIG. 12 is an end view of the bed in yet another operative position; and

FIG. 13 is a large-scale view of the details of FIG. 10.

SPECIFIC DESCRIPTION The bed according to the present invention, as shown in FIGS. lhas a base indicated generally at A and a mattress support indicated generally at B. This support B has a lower wall 3 on which are supported two upper plates 2 by means of sidewall 4, these walls 2 being at the longitudinal ends of the generally rectangular support B to either side of a central region 5 also supported by the sidewall 4 and by transverse bracing walls 4'.

FIG. 1 shows how the upper surface of the support B is formed by the central region 5 and flaps 7, and 7a to each side of this central section 5. A hinge 6 extending perpendicular to the longitudinal axis of support B and along the edge of the region 5 secures the section 7 and another hinge 17 parallel thereto secures the section 7a to the outer edge of the section 7, the outer edge of this section 7a being bent up as shown at 70' so that a mattress 19 carried on the two flaps 7a, two flaps 7, and the central region 5 cannot slip off.

Pivotal also on the hinge 6 and secured to the inner primary flap 7 is another flap 8 identical to flap 7 and inclined thereto at an angle equal approximately to 45, with a triangular section 7 serving to secure the two rigidly together and jointly pivotal about the axis of hinge 6. A bladder 9 is received between the second flap 8 and a wall 10 fixed to the support B and extending at an angle of approximately 45 to the upper surface thereof, but not on a plane intersecting the hinge 6. A hole 12 is formed in the support wall 3 to pass the bladder 9 and support 10. This bladder 9 can be inflated by a blower 16 through a valve operated from a control panel 50 so as to pivot the inner flap 7 upwardly about the hinge 6. It is possible to provide a C- section holding member 22 as shown to the right in FIG. 2 so as to hold the sections 7 and 7a parallel to each other. Otherwise the outer end of section 7a rides via rollers 18 on the upper wall 2 of the support B. This imparts the shape shown in FIG. 2 which is quite comfortable for sitting, since it holds the back straight and allows the legs to bend. Rollers 21 are provided at the ends of the lower walls 3 of the support B in order to guide it within the base A.

The base A is formed of a pair of metal or fiberglass shells 25 and 26, the latter being received on top of the former. The shell is formed at its base with a pair of concavities 36 receiving the wall 10 and the bladder 9 when the support B is in its lowermost position. This lower shell is formed with a reinforcement 38 at the center of each of its longitudinal edges and with a reinforcement 37 at the center of each of its transverse edges, the latter corresponding to the head and foot of the bed. The shell 26 is formed with a pair of holes 39 corresponding to the holes 12 and allowing the bladder 9 and wall 10 to drop into the concavities 36. In addition this shell 26 is formed with an inner wall 42 and an outer wall 43 constituting a rim around the support B, an I-I-section bar 47 serving to secure the two shells 25 and 26 together. The rim formed by the walls 42 and 43 is raised at the head and foot of the bed and serves to hold supplies.

Provided between the shell 26 and the lower wall 3 of the support B are four further bladders, 13a, 13b, 14a, and 14b, each provided in a corner of the bed. These bladders are also connectable via the valve 15 to the blower 16 so that they can be inflated so as to tip the support B about a longitudinal axis, as shown in FIG. 4. To this end the bladders are received in hollows 40 in the shell 26 so as to prevent them from being displaced, and the interiors of bladers 13a and 14a are connected together as are the bladers 13b and 14b so that the support B will be tipped uniformly from one end to the other, although it is possible to raise only a corner if this is particularly necessary. In addition it is possible to inflate all four of the bladders 13a 14b in order to elevate the entire mattress 19 up to the level of the upper rim of the bed. In this manner it is possible to examine the patient with ease, without having to move him from his bed and place him on an examination table.

The mattress 19 is provided with a central aperture 24 covered by a removable plug and giving access to a space 5' below the central region 5 in which a bedpan or the like may be provided. A door 5" is provided in the sidewall 4 so as to allow removal from the region 5' of the bedpan.

A leg 30 provided at=its lower end with a caster 33 is provided in the middle of each longitudinal edge of the bed at the reinforced portion 38. Each leg 30 has a pair of telescoping sections 30' and 30", the latter being received in the former with a resilient body 34 received in the top of the outer element 30 so as to absorb any shock which might be transmitted to the bed through the leg 30. The bed is also provided in the middle of each of its transverse edges, that is at the head and the foot of the bed, with a leg 27 terminating at its base in a large caster 29. This leg 27 comprises an outer tube 27 fixed between the wall 42 and 43 at the reinforced region 37, a middle tube 27", and a lower tube 27", all telescoped one within the other. The legs all fit very tightly one within the other so that it is possible to control them by means of a valve 27a at the upper tube 27 The valve 27a of each leg 27 is opened so as to allow the bed to be tipped as is shown in FIG. 2. Then the valve 27a is closed so as to retain within each leg that air which is trapped therein and thereby prevent the bed from resettling to a horizontal position. Of course it is also possible to provide hydraulic or mchanical means for securing the sections 27 and 27" relative to each other. It is advantageous to be able to tip the entire bed in the case of a hemorrhaging patient so as to reduce blood loss.

The rim of the bed is a useful holder for all kinds of devices often necessary in a hospital. For instance a series of snaps around the head part of the bed allows an oxygen tent to be securely fastened thereto.

The adjustable legs also make it possible to set the bed perfectly level even though the floor as shown in FIG. 2 may lie at plane P2 rather than at a plane Pl. It is frequently necessary, especially when giving transfusions or the like, that the patient be as level as possible.

The arrangement shown in FIGS. 6 through 13 is similar in function to that shown in FIGS. 1 through 5, and like reference numbers have been used for functionally identical structure throughout. In this arrangement however the side legs 30 are replaced by structures 57 having a large-diameter wheel 69 rotatable about an axis 72 transverse to the longitudinal axis of the bed. The entire wheel assembly 57 is itself pivotal about an axis 74 parallel to the longitudinal direction of the bed, and another small-diameter wheel 70 is pivoted on this structure 57 about an axis 73 perpendicular to both axis 72 and 74. The end legs 27 are replaced by legs 56 carrying at their lower ends yokes 64 on which are secured two casters 65, these yokes 64 being pivotal on the ends of the legs 56 about axes 66 which are horizontal and transverse to the axis of the bed. The upper end of leg 56 as shown in particular in FIG. 13 carries a drum 58 journaled on a plate 59 and wrapped by a band 60 having one end 60a secured to the plate 59 and another end 60b secured to a screw 62 operable by a handwheel 63 projecting from the respective end of the bed. A long tension spring 67 has one end hooked in one of the legs 56 and another end hooked in the other leg 56, so that this spring 67 tends to pull the legs in toward each other into vertical positions. Under normal circumstances as shown in FIGS. 7 and the legs extend at about 45to the horizontal so that the casters 65 lie under the end of the bed. Loosening of the brake bands 60 by rotation of the handwheels 63 allows the bed to be tipped as shown in FIG. 8, in which tipped position the handwheels 63 can again be tightened to lock the bed in place. The spring 67 will insure that all of the wheels 65 remain firmly in contact with the floor.

In order further to lower the bed it is possible as shown in FIGS. 11 and 9 to lock both of the end legs 56 in place and then pivot the wheel assemblies 57 inwardly as shown by arrow 75, whereupon the bed is held balanced on wheels 65 while one or both of the bands 60 is slowly released to drop the bed slowly down onto the wheels 70. In this position the bed is extremely low and can be readily pushed out of the way and stored, or a person lying on the ground can be readily easily loaded onto it. A locking mechanism 57' is provided to hold each foot 57 in the FIG. 11 position.

Instead of a single cushion 9 under a single flap 8 there are provided two interconnected bladders 9a and 9b to operate each flap 8. This is particularly useful in that it allows the leg 56 to swing all the way up against the base A.

The upper wall of the support B is formed with a central section 5 having a pair of hinges 6, a single flap 7 at the side of the bed used as the head and supported at its outer end on an end wall 86 pivotal on the bottom wall 3 about a hing 87. This it is possible to drop this end wall 67 down in the direction shown by arrow 88 and allow the flap 7 to assume the position shown in dot-dash lines in FIG. 10. Similarly the two flaps 7 and 70 similar to the flaps 7 and 7a of FIGS. 1-5 have at their outer end rollers 80 which ride on a track 82 pivoted at 83 on the wall 10 below the hinge 6. An end wall 84 supports this track 82, so that when it is dropped down as described above the flaps 7 and 70 can move between the positions shown in dashed lines in FIG. 10.

The base is provided at its end with U shaped walls 89 secured by snap fittings 90 so as to allow their removal when the bed is made. The base is formed with a skirt 55 that encases the bladders 9a and 9b and protects them.

The bed according to the present invention can be made relatively inexpensively as only a single relatively expensive operating mechanism, that is the blower 15,

need be provided. Bladders as used here are about the least expensive actuators available and they are capable of long use and can support relatively heavy loads. In addition the bladers have the distinct advantage that they act as a cushion, a feature very desirable in a bed.

I claim:

1. A bed comprising:

a mattress support having an elongated upper wall formed by a central section and a pair of end sections flanking said central section;

a mattress overlying said support;

a transversely extending hinge between each of said end sections and the corresponding edge of said central section;

a base underneath said support;

means for longitudinally tilting said base;

at least two transversely spaced inflatable first bladders between said base and said support;

means for inflating said first bladders for raising said support from said base and for tilting said support about a longitudinal axis relative to said base;

a flap underneath each of said end sections and pivotally fixed thereto, each end section extending at an angle to its respective flap and forming therewith an outwardly open V;

a second bladder between each of said flaps and said support; and

means for inflating said bladders for raising said end sections.

2. A bed comprising:

a mattress support having an elongated upper wall formed by a central section and a pair of end sections flanking said central section;

a transversely extending hinge between each of said end sections and the corresponding edge of said central section;

a base underneath said support;

at least two transversely spaced inflatable first bladders between said base and said support;

means for inflating said first bladders for raising said support from said base and for tilting said support about a longitudinal axis relative to said base;

a flap underneath each of said end sections and pivotally fixed thereto, each end section extending at an angle to its respective flap and forming therewith an outwardly open V;

a second bladder between each of said flaps and said support;

means for inflating said second bladders for raising said end sections;

two additional such transversely spaced first bladders, said support being generally rectangular and said first bladders each being arranged generally under a respective corner of said support, said support having a bottom wall formed with a pair of longitudinally spaced rigid support surfaces each receiving a respective second bladder, at least one of said end sections comprising a pair of planar longitudinally spaced inner and outer sections and a hinge articulation between said inner and outer sections, the respective second bladder engaging said one end section at said inner section only.

3. The bed defined in claim 2 wherein both of said end sections are formed of a pair of such inner and outer sections, said bed further comprising means engagable with said inner and outer sections for holding the respective outer section coplanar with the respective inner section.

4. The bed defined in claim 2, further comprising a pair of longitudinal legs each having an upper end engaging said base generally at the center of a respective longitudinal edge thereof, and a pair of transverse legs secured to said base and each having a lower end orientable generally below the center of a respective transverse edge of said support.

5. The bed defined in claim 4 wherein said transverse legs are adjustable to vary the distance between their lower ends and said base, said bed further comprising means for locking said transverse legs in position with their lower ends fixed relative to said base.

6. The bed defined in claim 5 wherein said transverse legs are each formed of a plurality of telescoping sections.

7. The bed defined in claim 5 wherein said transverse legs each have an upper end pivoted on said base, said means for locking including means for inhibiting pivoting of said transverse legs on said base.

8. The bed defined in claim 4 wherein said legs each have at least one wheel adapted to engage a floor support surface.

9. The bed defined in claim 4 wherein said longitudinal legs each include a su on structure pivoted about a longitudinal axis or ..d base and carrying a relatively large-diameter wheel rotatable about a transverse axis on said structure and a relatively small-diameter wheel rotatable about an axis on saidstructure coplanar with said axis of said large-diameter wheel, said structures being pivotable between first positions with said largediameter wheels engaging a floor support surface and a second position with said small-diameter wheels engaging a floor support surface, said base being closer to said floor support surface in said second positions of structures.

10. A bed comprising:

a mattress support having an elongated upper wall formed by a central section and a pair of end sections flanking said central section;

a transversely extending hinge between each of said end sections and the corresponding edge of said central section;

a base underneath said support;

at least two transversely spaced inflatable first bladders between said base and said support;

means for inflating said first bladders for raising said support from said base and for tilting said'support about a longitudinal axis relative to said base;

a flap underneath each of said end sections and pivotally fixed thereto, each end section extendingat an angle to its respective flap and forming therewith an outwardly open V;

a second bladder between each of said flaps and said support;

means for inflating said second bladders for raising said end sections,

two additional such transversely spaced first bladders, said support being generally rectangular and said first bladders each being arranged generally under a respective corner of said support, said support having a bottom wall formed with a pair of longitudinally spaced rigid support surfaces each receiving a respective second bladder, a mattress lying on said upper wall and being formed with an aperture above said central section, said support including a chamber beneath said aperture.

11. A bed comprising:

a mattress support having an elongated upper wall formed by a central section and a pair of end sections flanking said central section;

a transversely extending hinge between each of said end sections and the corresponding edge of said central section;

a base underneath said support;

at least two transversely spaced inflatable first bladders between said base and said support;

means for inflating said first bladders for raising said support from said base and for tilting said support about a longitudinal axis relative to said base;

a flap underneath each of said end sections and pivotally fixed thereto, each end section extending at an angle to its respective flap and forming therewith an outwardly open V;

a second bladder between each of said flaps and said support;

means for inflating said second bladders for raising said end sections;

two additional such transversely spaced first bladders, said support being generally rectangular and said first bladders each being arranged generally unders a respective corner of said support, said support having a bottom wall formed with a pair of longitudinally spaced rigid support surfaces each receiving a respective second bladder, said support includes generally vertical side walls extending between said top and bottom walls, said bed further comprising hinge means for flattening at least one of said side walls down on top of said bottom wall for pivoting the respective end section of said top wall down into engagement with said bottom wall. 

1. A bed comprising: a mattress support having an elongated upper wall formed by a central section and a pair of end sections flanking said central section; a mattress overlying said support; a transversely extending hinge between each of said end sections and the corresponding edge of said central section; a base underneath said support; means for longitudinally tilting said base; at least two transversely spaced inflatable first bladders between said base and said support; means for inflating said first bladders for raising said support from said base and for tilting said support about a longitudinal axis relative to said base; a flap underneath each of said end sections and pivotally fixed thereto, each end section extending at an angle to its respective flap and forming therewith an outwardly open V; a second bladder between each of said flaps and said support; and means for inflating said bladders for raiSing said end sections.
 2. A bed comprising: a mattress support having an elongated upper wall formed by a central section and a pair of end sections flanking said central section; a transversely extending hinge between each of said end sections and the corresponding edge of said central section; a base underneath said support; at least two transversely spaced inflatable first bladders between said base and said support; means for inflating said first bladders for raising said support from said base and for tilting said support about a longitudinal axis relative to said base; a flap underneath each of said end sections and pivotally fixed thereto, each end section extending at an angle to its respective flap and forming therewith an outwardly open V; a second bladder between each of said flaps and said support; means for inflating said second bladders for raising said end sections; two additional such transversely spaced first bladders, said support being generally rectangular and said first bladders each being arranged generally under a respective corner of said support, said support having a bottom wall formed with a pair of longitudinally spaced rigid support surfaces each receiving a respective second bladder, at least one of said end sections comprising a pair of planar longitudinally spaced inner and outer sections and a hinge articulation between said inner and outer sections, the respective second bladder engaging said one end section at said inner section only.
 3. The bed defined in claim 2 wherein both of said end sections are formed of a pair of such inner and outer sections, said bed further comprising means engagable with said inner and outer sections for holding the respective outer section coplanar with the respective inner section.
 4. The bed defined in claim 2, further comprising a pair of longitudinal legs each having an upper end engaging said base generally at the center of a respective longitudinal edge thereof, and a pair of transverse legs secured to said base and each having a lower end orientable generally below the center of a respective transverse edge of said support.
 5. The bed defined in claim 4 wherein said transverse legs are adjustable to vary the distance between their lower ends and said base, said bed further comprising means for locking said transverse legs in position with their lower ends fixed relative to said base.
 6. The bed defined in claim 5 wherein said transverse legs are each formed of a plurality of telescoping sections.
 7. The bed defined in claim 5 wherein said transverse legs each have an upper end pivoted on said base, said means for locking including means for inhibiting pivoting of said transverse legs on said base.
 8. The bed defined in claim 4 wherein said legs each have at least one wheel adapted to engage a floor support surface.
 9. The bed defined in claim 4 wherein said longitudinal legs each include a support structure pivoted about a longitudinal axis on said base and carrying a relatively large-diameter wheel rotatable about a transverse axis on said structure and a relatively small-diameter wheel rotatable about an axis on said structure coplanar with said axis of said large-diameter wheel, said structures being pivotable between first positions with said large-diameter wheels engaging a floor support surface and a second position with said small-diameter wheels engaging a floor support surface, said base being closer to said floor support surface in said second positions of structures.
 10. A bed comprising: a mattress support having an elongated upper wall formed by a central section and a pair of end sections flanking said central section; a transversely extending hinge between each of said end sections and the corresponding edge of said central section; a base underneath said support; at least two transversely spaced inflatable first bladders between said base and said support; means for inflating said fiRst bladders for raising said support from said base and for tilting said support about a longitudinal axis relative to said base; a flap underneath each of said end sections and pivotally fixed thereto, each end section extending at an angle to its respective flap and forming therewith an outwardly open V; a second bladder between each of said flaps and said support; means for inflating said second bladders for raising said end sections, two additional such transversely spaced first bladders, said support being generally rectangular and said first bladders each being arranged generally under a respective corner of said support, said support having a bottom wall formed with a pair of longitudinally spaced rigid support surfaces each receiving a respective second bladder, a mattress lying on said upper wall and being formed with an aperture above said central section, said support including a chamber beneath said aperture.
 11. A bed comprising: a mattress support having an elongated upper wall formed by a central section and a pair of end sections flanking said central section; a transversely extending hinge between each of said end sections and the corresponding edge of said central section; a base underneath said support; at least two transversely spaced inflatable first bladders between said base and said support; means for inflating said first bladders for raising said support from said base and for tilting said support about a longitudinal axis relative to said base; a flap underneath each of said end sections and pivotally fixed thereto, each end section extending at an angle to its respective flap and forming therewith an outwardly open V; a second bladder between each of said flaps and said support; means for inflating said second bladders for raising said end sections; two additional such transversely spaced first bladders, said support being generally rectangular and said first bladders each being arranged generally unders a respective corner of said support, said support having a bottom wall formed with a pair of longitudinally spaced rigid support surfaces each receiving a respective second bladder, said support includes generally vertical side walls extending between said top and bottom walls, said bed further comprising hinge means for flattening at least one of said side walls down on top of said bottom wall for pivoting the respective end section of said top wall down into engagement with said bottom wall. 